Study on the Influence of Different Solidified Materials on the Migration and Transformation of Cd in Polluted Sediments
Heavy metal contaminated sediment is a kind of sediment difficult to be treated in dredging sediment.It is not only necessary to improve its mechanical and physical and chemical properties,but also to consider the migration and transformation of heavy metals in the sediment.Exogenous Cd2+ was added to the bottom mud of Shima River for curing,and the combination formula of different solidified materials and modified materials was added at the same time to study the migration and transformation of Cd in the bottom mud by solidified materials and modified materials while improving the physical and chemical properties of the bottom mud.The results showed that:After adding exogenous Cd2+ to the sediment,the transformation of Cd form in the sediment was basically stable when the curing period reached 7 days.When cement-based curing materials are added,it is helpful to transform the form of Cd in the sediment from unstable state to stable state,and the higher the amount of cement added,the lower the content of Cd in the sediment leaching solution.Through comparative analysis,it can be concluded that the curing formula of Shima River sediment should be"40 kg/m3 cement+5 kg/m3 lime + 5 kg/m3"gypsum.The addition of humic acid and straw meal can also help the conversion of Cd from unstable state to stable state in the sediment,and the addition amount of straw meal and humic acid should be 200 g/kg and 5～10 g/kg respectively.The results of this study can provide key parameters and scientific basis for the resource utilization of heavy metal contaminated sediment.
Solidified materialsCdPolluted sedimentsMigration and transformationLeaching solution
万方数据
维普
